Soaps are also prepared in which large proportions of fine sharp sand, or of powdered pumice, are incorporated, and these substances, by their abrading action, powerfully assist the detergent influence of the soap on hands much begrimed by manufacturing operations.'
Mineral, vegetable and animal substances, by means of tools and apparatus of stone, wood and bone - tools for cutting, or edged tools; tools for abrading and smoothing the surfaces of substances, like planes, rasps and sandpaper; tools for striking, that is, pounding for the sake of pounding, or for crushing and fracturing violently; perforating tools; devices for grasping and holding firmly.
Now feet have extra tough skin, so just imagine how abrading sand can affect the softer skin on your arms and torso.
Cutting and engraving are mechanical processes for producing decorative effects by abrading the surface of the glass when cold.